FILM Beware Canadians — they may walk softly, but they carry a big hockey stick. The country next door has always had a bigger influence on American life than generally thought, especially at the movies. Mary Pickford, the medium's first superstar, was Canadian; so, a century later, are Ryans Gosling and Reynolds, Jim Carrey, Ellen Page, Rachel McAdams, and Seth Rogen. Canadians have directed a lot of seemingly very American films, from 1982's Porky's to this year's Prisoners.

Now there's Dallas Buyers Club, the first all-US feature (though not the first English-language one) from Jean-Marc Vallée. He first made a splash in 2005 with C.R.A.Z.Y., which seemed an archetype of the flashy, coming-of-age themed debut feature — even if, in fact, it took him 42 years and three prior features to get there.

Like fellow Quebecker Denis Villeneuve (of Prisoners and 2010's Incendies), Vallée has evolved beyond flashiness, or maybe since C.R.A.Z.Y. he just hasn't had a subject that seemed to call for it. Which is not to say Dallas is entirely sober — its characters partake from the gamut of altering substances, over-the-counter and otherwise. But this is a movie about AIDS, so the purely recreational good times must eventually crash to an end.

Which they do pretty quickly. We first meet Ron Woodroof (Matthew McConaughey) in 1986, when he's living one kind of red-blooded American Dream: a Texas good ol' boy working the rodeo circuit, chasing skirts, partying nonstop. Not feeling quite right, he visits a doctor, who informs him that he is HIV-positive and probably has no more than 30 days left on this mortal plane. His response is "I ain't no faggot, motherfucker" — and increased partying that he barely survives.

Afterward, he pulls himself together enough to visit somewhere you suspect he's seldom been before — the public library — and research his options. It appears the only significant treatment drug is AZT, which isn't even on the market yet; it's just being tested on patient groups he'd be lucky to be a part of. Being a born hustler disinterested in such formal roadblocks, Ron simply bribes a hospital attendant into raiding its trial supply for him. But Ron discovers the hard way what many first-generation AIDS patients did — that AZT is itself toxic, and in the high doses originally administered could cause much more harm than good to embattled immune systems.

He ends up in a Mexican clinic run by a disgraced American physician (Griffin Dunne) who doesn't have to bother with the more stringent drug regulations up north, and in any case recommends a regime consisting mostly of vitamins and herbal treatments. Reasonably hale again after three months, Woodroof realizes a commercial opportunity here: He can smuggle such variably legal supplies in bulk to those who'll pay any price for some hope back home in Texas. Yes, they're mostly fay-guts. But a buck is a buck.

Finding he's viewed with high suspicion peddling his wares to a plague-embattled gay community, he acquires as liaison and business partner Rayon (Jared Leto), a willowy cross-dresser in the Candy Darling mode who won't tolerate his homophobia, but requires considerable tolerance for his/her non medicinal drug usage. When the authorities keep cracking down on their trade, savvy Ron takes a cue from gay activists in Manhattan and creates a law-evading "buyers club," in which members pay monthly dues rather than paying directly for pharmaceutical goods.